DESCRIPTION (Adapted from the Applicant's Description):It has long been accepted that prolonged prenatal insult and subsequent fetal compromise can alter the normal development of the fetal CNS in ways that produce vulnerability to subsequent neurological impairment. Two global issues addressed in the proposed studies are: development of new assessment methodologies in the perinatal period, and evaluation of the efficacy of these methodologies for predicting impairments in neurologic development and/or SIDS. These assessments will be conducted in an urban low-SES population presenting additional risk factors for poor neurological outcome and SIDS, and in a Native American population on the Pine Ridge Reservation in South Dakota which is at unusually high risk for SIDS and other manifestations of neurologic damage. In one set of studies the investigators will apply new assessment methods for evaluating the integrity of cardiorespiratory control systems in the fetus, track the maturation of these measures through the perinatal period, and then determine their relationship to outcome at one year of age. Another series of experiments will focus on the early development of reflex cardiovascular adjustment to postural manipulations, cardiorespiratory responses to salient auditory stimuli, and cortical evoked responses. There are two facets to the strategy for assessing the sensitivity of the measures. The first is to test the ability of the measures to discriminate risk groups (maternal smoking and anemia) that vary in their degree of compromise to the fetus and newborn. The second will be to determine whether the measured profiles of physiological development predict neurologic outcome of the study populations assessed at one year of age. There are three primary Aims of the proposed studies. Aim 1. To determine whether indices of neural regulation of cardiorespiratory activity measured in the perinatal period will distinguish populations at risk for developing neurologic disorders and/or SIDS. Aim 2. To determine whether a profile of state dependent evoked cardiorespiratory and/or cortical responses made through the perinatal period will distinguish populations of fetuses and infants at-risk for developing neurologic disorders and/or SIDS. Aim 3. To determine whether indices of neural regulation of cardiorespiratory activity measured in Native American newborns will distinguish those infants at greatest risk for developing neurologic disorders and/or SIDS.